Wearable cardiac defibrillator system emitting CPR prompts

ABSTRACT

A wearable cardiac defibrillator (“WCD”) system may include a support structure that a patient can wear, an energy storage module that can store an electrical charge, and a discharge circuit that can discharge the electrical charge through the patient so as to shock him or her, while the patient is wearing the support structure. Embodiments may actively take into account bystanders, both to protect them from an inadvertent shock, and also to enlist their help. In some embodiments the WCD system includes a speaker system that transmits a sound designed to assist a bystander to perform CPR. Optionally CPR chest compressions received by the patient can be further detected, and feedback can be given. In embodiments, a WCD system may include a user interface that can be controlled to output CPR prompts tailored to a skill level of the bystander.

CROSS REFERENCE TO RELATED PATENT APPLICATIONS

This patent application claims priority from U.S. Provisional PatentApplication Ser. No. 61/955,389, filed on Mar. 19, 2014, the disclosureof which is hereby incorporated by reference for all purposes.

BACKGROUND

When people suffer from some types of heart arrhythmias, the result maybe that blood flow to various parts of the body is reduced. Somearrhythmias may even result in a Sudden Cardiac Arrest (SCA). SCA canlead to death very quickly, e.g. within 10 minutes, unless treated inthe interim.

Some people have an increased risk of SCA. People at a higher riskinclude individuals who have had a heart attack, or a prior SCA episode.A frequent recommendation is for these people to receive an ImplantableCardioverter Defibrillator (“ICD”). The ICD is surgically implanted inthe chest, and continuously monitors the person's electrocardiogram(“ECG”). If certain types of heart arrhythmias are detected, then theICD delivers an electric shock through the heart.

After being identified as having an increased risk of an SCA, and beforereceiving an ICD, these people are sometimes given a wearable cardiacdefibrillator (“WCD”) system. A WCD system typically includes a harness,vest, or other garment for wearing by the patient. The system includes adefibrillator and external electrodes, which are attached on the insideof the harness, vest, or other garment. When a patient wears a WCDsystem, the external electrodes may then make good electrical contactwith the patient's skin, and therefore can help monitor the patient'sECG. If a shockable heart arrhythmia is detected, then the defibrillatorof the WCD system delivers the appropriate electric shock through thepatient's body, and thus through the heart.

A wearable defibrillator system (WCD) system will typically be wornunder the outer garments of a patient. If the patient collapses, abystander might not help; even if they mean to help, they might not knowabout WCD systems, or what to do. A bystander trained in CardioPulmonary Resuscitations (CPR) might know to try to administer CPR chestcompressions and ventilations; this intended rescuer, however, might notknow that the patient is already wearing a WCD system, which could befurther preparing to administer an electric shock through the patient,and which could be dangerous to whoever is touching the patient at thetime.

BRIEF SUMMARY

The present description gives instances of wearable cardiacdefibrillator (“WCD”) systems, software, and methods, the use of whichmay help overcome problems and limitations of the prior art. A WCDsystem may include a support structure that a patient can wear, anenergy storage module that can store an electrical charge, and adischarge circuit that can discharge the electrical charge through thepatient so as to shock him or her, while the patient is wearing thesupport structure. Embodiments may actively take into accountbystanders, both to protect them from an inadvertent shock, and also toenlist their help.

In embodiments, a WCD system may include a speaker system and a memory.Prompts may have been saved in advance in the patient's own voice, andstored in the memory. In case of an emergency, the prompts may be playedby the speaker system in the patient's own voice, and heard by abystander.

In embodiments, a WCD system may include a user interface or acapacitance meter. Upon sensing that the patient is being touched by aperson other than the patient, the WCD system may prevent dischargingthe electrical charge, so as to protect an intended rescuer from beingshocked.

In embodiments, a WCD system may include a proximity detector and aspeaker system. Upon inferring that no bystander is nearby, the speakersystem may transmit a sound at a higher intensity than otherwise, hopingto attract attention.

In embodiments, a WCD system may include a proximity detector and aspeaker system. Upon inferring that a bystander is closer than athreshold, the speaker system may transmit a sound with a first content,as opposed to a sound with a second content. The first content could beinstructing the bystander, while the second content could be requestingthat a bystander who is hopefully close enough become engaged.

In embodiments, a WCD system may be able to detect whether the patientis suffering from Pulseless Electrical Activity (P.E.A.). In suchembodiments, the WCD system may announce it, and possibly even dischargethe charge through the patient anyway, as a last resort. A bystander'shelp may be requested and, if received, shocking might become notnecessary.

In embodiments, a WCD system may include a speaker system, and request abystander to place a mobile communication device close to the speakersystem, sometimes after first dialing a specific telephone number. Thespeaker system may transmit sounds that communicate aspects of thepatient and the event, and which may be thus received by a remote carecenter over a wireless communication link.

In embodiments, a WCD system may include a speaker system that transmitsa sound, which has periodic contents that are designed to assist abystander to perform CPR. Optionally CPR chest compressions are furtherdetected, and feedback can be given. In embodiments, a WCD system mayinclude a user interface that can differentiate among bystanders. Theuser interface may output CPR prompts that are tailored to a skill levelof the bystander.

In embodiments, a WCD system may include a microphone. It might be readyto deliver a shock, but may not if it hears from a bystander a presetdelaying word, such as “NO”.

In embodiments, a WCD system may include a microphone. It might be readyto deliver a shock, but may first wait before doing so until it hearsfrom a bystander a preset ready word, such as: “CLEAR”.

In embodiments, a WCD system may include a speaker system that transmitsa sound requesting a bystander to speak. The WCD system may include amicrophone and a memory to sense what the bystander may say, and recordit. The sensed speech may be even interpreted for operation.

In embodiments, a WCD system may include a cancel switch that can cancelan impending shock, and ways to determine whether the cancel switch hasbeen actuated inappropriately, in which case the actuation may beignored. A motion detector may generate motion data, and the actuationmay be ignored if the motion data meets a spuriousness threshold.

In embodiments, a WCD system may include a cancel switch that can cancelan impending shock, and ways to prevent it from being actuated withoutprior authorization. The cancel switch can be configured to be actuatedin conjunction with receiving a validation input, so as to authenticatethe person who is actuating it. The validation input can be a codeentered in a keyboard, or a fingerprint scanned in a fingerprint reader.

In embodiments, a WCD system may include a user interface, of which allor portions can be accessed by a bystander who can enter a correctvalidation input. The validation input can be a code entered in akeyboard, or a fingerprint scanned in a fingerprint reader.

Embodiments also include combinations of the above.

These and other features and advantages of this description will becomemore readily apparent from the Detailed Description, which proceeds withreference to the associated drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of components of a sample wearable cardiacdefibrillator (WCD) system, made according to embodiments.

FIG. 2 is a diagram showing sample components of an externaldefibrillator, such as the one belonging in the WCD system of FIG. 1,and which is made according to embodiments.

FIG. 3 is a diagram showing a collection of sample components ofWearable Cardiac Defibrillator systems included in many embodiments.

FIG. 4 is a diagram of a sample scene where a WCD system is used with abystander, and which sounds in the patient's own voice according toembodiments.

FIG. 5 is flowchart for illustrating sample methods according toembodiments.

FIGS. 6 and 7 are diagrams of sample scenes for illustrating differentmodes of operation of an embodiment.

FIG. 8 is a flowchart for illustrating sample methods according toembodiments.

FIGS. 9 and 10 are diagrams of sample scenes for illustrating differentmodes of operation of an embodiment.

FIG. 11 is a flowchart for illustrating sample methods according toembodiments.

FIG. 12 is a diagram of a sample scene where a patient who could besuffering from Pulseless Electrical Activity is wearing a WCD systemthat is made according to embodiments.

FIG. 13 is a flowchart for illustrating sample P.E.A. methods accordingto embodiments.

FIG. 14 is a flowchart for illustrating sample P.E.A. methods accordingto embodiments.

FIGS. 15 and 16 are diagrams of sample successive scenes forillustrating how a bystander may help with a mobile communication deviceaccording to embodiments.

FIG. 17 is a flowchart for illustrating sample methods according toembodiments.

FIG. 18 is a flowchart for illustrating a sample dual mode operationaccording to embodiments.

FIG. 19 is a diagram of a scene where a sample WCD system transmitssounds that are designed to assist a bystander to perform CPR accordingto embodiments.

FIG. 20 is a flowchart for illustrating sample methods according toembodiments.

FIG. 21 is a flowchart for illustrating sample methods according toembodiments.

FIG. 22 is a diagram of a scene where a sample WCD system according toembodiments is prevented from shocking a patient if it hears a delayingword such as “NO”.

FIG. 23 is a diagram of a scene where a sample WCD system according toembodiments shocks a patient only after hearing a preset ready word,such as “CLEAR”.

FIG. 24 is a diagram of a scene where a sample WCD system according toembodiments asks a bystander to speak.

FIG. 25 is a flowchart for illustrating sample methods according toembodiments.

FIG. 26 is a flowchart for illustrating sample methods according toembodiments.

FIG. 27 is a flowchart for illustrating sample methods according toembodiments.

FIG. 28 is a flowchart for illustrating sample methods according toembodiments.

DETAILED DESCRIPTION

As has been mentioned, the present description is about wearable cardiacdefibrillator (“WCD”) systems, software, and methods. Embodiments arenow described in more detail.

A wearable cardiac defibrillator (WCD) system made according toembodiments has a number of components. These components can be providedseparately as modules that can be interconnected, or can be combinedwith other components, etc.

A component of a WCD system can be a support structure, which isconfigured to be worn by the patient. The support structure can be anystructure suitable for wearing, such as a harness, a vest, ahalf-vest—for example over the left side of the torso that positionselectrodes on opposite sides of the heart, one or more belts that areconfigured to be worn horizontally or possibly vertically over ashoulder, another garment, and so on. The support structure can beimplemented in a single component, or multiple components. For example,a support structure may have a top component resting on the shoulders,for ensuring that the defibrillation electrodes will be in the rightplace for defibrillating, and a bottom component resting on the hips,for carrying the bulk of the weight of the defibrillator. A singlecomponent embodiment could be with a belt around at least the torso.Other embodiments could use an adhesive structure or another way forattaching to the person, without encircling any part of the body. Therecan be other examples.

FIG. 1 depicts components of a WCD system made according to embodiments,as it might be worn by a person 82. A person such as person 82 may alsobe referred to as a patient and/or wearer, since that person wearscomponents of the WCD system. Patient 82 may wear garments, one or moreof which can be associated with a WCD system. In addition, a portion ofan outer garment 99 is shown. Outer garment 99 might be obscuring theWCD system that patient 82 is wearing.

In FIG. 1, a generic support structure 170 is shown relative to the bodyof person 82, and thus also relative to his or her heart 85. Structure170 could be a harness, a vest, a half-vest, one or more belts, or agarment, etc., as per the above. Structure 170 could be implemented in asingle component, or multiple components, and so on. Structure 170 iswearable by person 82, but the manner of wearing it is not depicted, asstructure 170 is depicted only generically in FIG. 1.

A wearable cardiac defibrillator (WCD) system is configured todefibrillate a patient who is wearing it, by delivering electricalcharge to the patient's body in the form of an electric shock deliveredin one or more pulses. FIG. 1 shows a sample external defibrillator 100,and sample defibrillation electrodes 104, 108, which are coupled toexternal defibrillator 100 via electrode leads 105. Defibrillator 100and defibrillation electrodes 104, 108 are coupled to support structure170. As such, many of the components of defibrillator 100 can betherefore coupled to support structure 170. When defibrillationelectrodes 104, 108 make good electrical contact with the body of person82, defibrillator 100 can administer, via electrodes 104, 108, a brief,strong electric pulse 111 through the body. Pulse 111, also known as adefibrillation shock or therapy shock, is intended to go through andrestart heart 85, in an effort to save the life of person 82. Pulse 111can further include one or more pacing pulses, and so on.

A prior art defibrillator typically decides whether to defibrillate ornot based on an electrocardiogram (“ECG”) signal of the patient.However, defibrillator 100 can defibrillate, or not defibrillate, alsobased on other inputs.

The WCD system may optionally include an outside monitoring device 180.Device 180 is called an “outside” device because it is provided as astandalone device, for example not within the housing of defibrillator100. Device 180 can be configured to monitor at least one localparameter. A local parameter can be a parameter of patient 82, or aparameter of the WCD system, or a parameter of the environment, as willbe described later in this document.

Optionally, device 180 is physically coupled to support structure 170.In addition, device 180 can be communicatively coupled with othercomponents, which are coupled to support structure 170. Suchcommunication can be by a communication module, as will be deemedapplicable by a person skilled in the art in view of this disclosure.

Notwithstanding the complexity and sophistication of a WCD system, itshould not be forgotten that it might all be covered under outer garment99 of patient 82. Moreover, such systems are not common, at least today.Accordingly, if patient 82 is found unconscious by an untrainedbystander, the bystander might reasonably think that patient 82 hasfainted. Such a bystander might not reasonably suspect that this patienthas suffered from a cardiac related ailment, and is wearing an activeWCD system that can deliver an electric shock to patient 82, and thusalso to anyone touching patient 82. Moreover, when a person has fainted,it is customary to assist them by opening their shirt, for assistingtheir breathing. Upon seeing a harness of WCD system snugly around thechest of person 82, a well-meaning bystander might surmise that this WCDis further constricting the breathing of person 82, and might furthertry to loosen it.

FIG. 2 is a diagram showing components of an external defibrillator 200,made according to embodiments. These components can be, for example,included in external defibrillator 100 of FIG. 1. The components shownin FIG. 2 can be provided in a housing 201, which is also known ascasing 201.

External defibrillator 200 is intended for a patient who would bewearing it, such as person 82 of FIG. 1. Defibrillator 200 may furtherinclude a user interface 270 for a user 282. User 282 can be patient 82,also known as wearer 82. Or user 282 can be a local rescuer at thescene, such as a bystander who might offer assistance, or a trainedperson. Or, user 282 might be a remotely located trained caregiver incommunication with the WCD system.

User interface 270 can be made in any number of ways. User interface 270may include output devices, which can be visual, audible or tactile, forcommunicating to a user. For example, an output device can be a light,or a screen to display what is detected and measured, and provide visualfeedback to rescuer 282 for their resuscitation attempts, and so on.Another output device can be a speaker, which can be configured to issuevoice prompts, etc. Sounds, images, vibrations, and anything that can beperceived by user 282 can also be called human perceptible indications.User interface 270 may also include input devices for receiving inputsfrom users. Such input devices may include various controls, such aspushbuttons, keyboards, touchscreens, a microphone, validation inputdevices such as a keypad, a fingerprint reader, and so on. An inputdevice can be a cancel switch, which is sometimes called a “live-man”switch. In some embodiments, actuating the cancel switch can prevent theimpending delivery of a shock.

Defibrillator 200 may include an internal monitoring device 281. Device281 is called an “internal” device because it is incorporated withinhousing 201. Monitoring device 281 can monitor patient parameters,patient physiological parameters, system parameters and/or environmentalparameters, all of which can be called patient data. In other words,internal monitoring device 281 can be complementary or an alternative tooutside monitoring device 180 of FIG. 1. Allocating which of the systemparameters are to be monitored by which monitoring device can be doneaccording to design considerations.

Patient physiological parameters include, for example, thosephysiological parameters that can be of any help in detecting by the WCDsystem whether the patient is in need of a shock, plus optionally theirmedical history and/or event history. Examples of such parametersinclude the patient's ECG, blood oxygen level, blood flow, bloodpressure, blood perfusion, pulsatile change in light transmission orreflection properties of perfused tissue, heart sounds, heart wallmotion, breathing sounds and pulse. Accordingly, the monitoring devicecould include a perfusion sensor, a pulse oximeter, a Doppler device fordetecting blood flow, a cuff for detecting blood pressure, an opticalsensor, illumination detectors and perhaps sources for detecting colorchange in tissue, a motion sensor, a device that can detect heart wallmovement, a sound sensor, a device with a microphone, an SpO2 sensor,and so on. Pulse detection is taught at least in Physio-Control's U.S.Pat. No. 8,135,462, which is hereby incorporated by reference in itsentirety. In addition, a person skilled in the art may implement otherways of performing pulse detection.

In some embodiments, the local parameter is a trend that can be detectedin a monitored physiological parameter of patient 82. A trend can bedetected by comparing values of parameters at different times.Parameters whose detected trends can particularly help a cardiacrehabilitation program include: a) cardiac function (e.g. ejectionfraction, stroke volume, cardiac output, etc.); b) heart ratevariability at rest or during exercise; c) heart rate profile duringexercise and measurement of activity vigor, such as from the profile ofan accelerometer signal and informed from adaptive rate pacemakertechnology; d) heart rate trending; e) perfusion, such as from SpO2 orCO2; f) respiratory function, respiratory rate, etc.; g) motion, levelof activity; and so on. Once a trend is detected, it can be storedand/or reported via a communication link, along perhaps with a warning.From the report, a physician monitoring the progress of patient 82 willknow about a condition that is either not improving or deteriorating.

Patient state parameters include recorded aspects of patient 82, such asmotion, posture, whether they have spoken recently plus maybe also whatthey said, and so on, plus optionally the history of these parameters.Or, one of these monitoring devices could include a location sensor suchas a Global Positioning System (GPS) location sensor. Such a sensor canabout the location, plus a speed can be detected as a rate of change oflocation over time. Many motion detectors output a motion signal that isindicative of the motion of the detector, and thus of the patient'sbody. Patient state parameters can be very helpful in narrowing down thedetermination of whether SCA is indeed taking place.

A wearable cardiac defibrillator (WCD) system made according toembodiments may include a motion detector. In embodiments, a motiondetector can be implemented within monitoring device 180 or monitoringdevice 281. Such a motion detector can be configured to detect a motionevent. In response, the motion detector may render or generate from thedetected motion event a motion detection input that can be received by asubsequent device or functionality. A motion event can be defined as isconvenient, for example a change in motion from a baseline motion orrest, etc. Such a motion detector can be made in many ways as is knownin the art, for example by using an accelerometer.

System parameters of a WCD system can include system identification,battery status, system date and time, reports of self-testing, recordsof data entered, records of episodes and intervention, and so on.

Environmental parameters can include ambient temperature and pressure. Ahumidity sensor may provide information as to whether it is likelyraining. Presumed patient location could also be considered anenvironmental parameter. The patient location could be presumed ifmonitoring device 180 or 281 includes a location sensor as per theabove, such as a GPS location sensor.

Defibrillator 200 typically includes a defibrillation port 210, such asa socket in housing 201. Defibrillation port 210 includes electricalnodes 214, 218. Leads of defibrillation electrodes 204, 208, such asleads 105 of FIG. 1, can be plugged in defibrillation port 210, so as tomake electrical contact with nodes 214, 218, respectively. It is alsopossible that defibrillation electrodes 204, 208 are connectedcontinuously to defibrillation port 210, instead. Either way,defibrillation port 210 can be used for guiding, via electrodes, to thewearer the electrical charge that has been stored in energy storagemodule 250. The electric charge will be the shock for defibrillation,pacing, and so on.

Defibrillator 200 may optionally also have an ECG port 219 in housing201, for plugging in sensing electrodes 209, which are also known as ECGleads. It is also possible that sensing electrodes 209 can be connectedcontinuously to ECG port 219, instead. Sensing electrodes 209 can helpsense an ECG signal, e.g. a 12-lead signal, or a signal from a differentnumber of leads, especially if they make good electrical contact withthe body of the patient. Sensing electrodes 209 can be attached to theinside of support structure 170 for making good electrical contact withthe patient, similarly as defibrillation electrodes 204, 208.

Defibrillator 200 also includes a measurement circuit 220. Measurementcircuit 220 receives physiological signals of the patient from ECG port219, if provided. Even if defibrillator 200 lacks ECG port 219,measurement circuit 220 can obtain physiological signals through nodes214, 218 instead, when defibrillation electrodes 204, 208 are attachedto the patient. In these cases, the patient's ECG signal can be sensedas a voltage difference between electrodes 204, 208. Plus, impedancebetween electrodes 204, 208 and/or the connections of ECG port 219 canbe sensed. Sensing the impedance can be useful for detecting, amongother things, whether these electrodes 204, 208 and/or sensingelectrodes 209 are not making good electrical contact with the patient'sbody. These patient physiological signals can be sensed, when available.Measurement circuit 220 can then render or generate information aboutthem as physiological inputs, data, other signals, etc. More strictlyspeaking, the information rendered by measurement circuit 220 is outputfrom it, but this information can be called an input because it isreceived by a subsequent device or functionality as an input.

Defibrillator 200 also includes a processor 230. Processor 230 may beimplemented in any number of ways. Such ways include, by way of exampleand not of limitation, digital and/or analog processors such asmicroprocessors and digital-signal processors (DSPs); controllers suchas microcontrollers; software running in a machine; programmablecircuits such as Field Programmable Gate Arrays (FPGAs),Field-Programmable Analog Arrays (FPAAs), Programmable Logic Devices(PLDs), Application Specific Integrated Circuits (ASICs), anycombination of one or more of these, and so on.

Processor 230 can be considered to have a number of modules. One suchmodule can be a detection module 232. Detection module 232 can include aventricular fibrillation (“VF”) detector. The patient's sensed ECG frommeasurement circuit 220, which can be available as physiological inputs,data, or other signals, may be used by the VF detector to determinewhether the patient is experiencing VF. Detecting VF is useful, becauseVF results in SCA. Detection module 232 can also include a ventriculartachycardia (“VT”) detector, and so on.

Another such module in processor 230 can be an advice module 234, whichgenerates advice for what to do. The advice can be based on outputs ofdetection module 232. There can be many types of advice according toembodiments. In some embodiments, the advice is a shock/no shockdetermination that processor 230 can make, for example via advice module234. The shock/no shock determination can be made by executing a storedShock Advisory Algorithm. A Shock Advisory Algorithm can make a shock/noshock determination from one or more of ECG signals that are capturedaccording to embodiments, and determining whether or not a shockcriterion or shock condition is met. The determination can be made froma rhythm analysis of the captured ECG signal or otherwise.

In some embodiments, when the decision is to shock, an electrical chargeis delivered to the patient. Delivering the electrical charge is alsoknown as discharging. Shocking can be for defibrillation, pacing, and soon.

Processor 230 can include additional modules, such as other module 236,for other functions. In addition, if internal monitoring device 281 isindeed provided, it may be operated in part by processor 230, etc.

Defibrillator 200 optionally further includes a memory 238, which canwork together with processor 230. Memory 238 may be implemented in anynumber of ways. Such ways include, by way of example and not oflimitation, volatile memories, nonvolatile memories (NVM), read-onlymemories (ROM), random access memories (RAM), magnetic disk storagemedia, optical storage media, smart cards, flash memory devices, anycombination of these, and so on. Memory 238 is thus a non-transitorystorage medium. Memory 238, if provided, can include programs forprocessor 230, which processor 230 may be able to read, and execute.More particularly, the programs can include sets of instructions in theform of code, which processor 230 may be able to execute upon reading.Executing is performed by physical manipulations of physical quantities,and may result in the functions, processes, actions and/or methods to beperformed, and/or the processor to cause other devices or components orblocks to perform such functions, processes, actions and/or methods. Theprograms can be operational for the inherent needs of processor 230, andcan also include protocols and ways that decisions can be made by advicemodule 234. In addition, memory 238 can store prompts for user 282, ifthey are a local rescuer. Moreover, memory 238 can store data. The datacan include patient data, system data and environmental data, forexample as learned by internal monitoring device 281 and outsidemonitoring device 180. The data can be stored in memory 238 before it istransmitted out of defibrillator 200, or stored there after it isreceived by it.

Defibrillator 200 may also include a power source 240. To enableportability of defibrillator 200, power source 240 typically includes abattery. Such a battery is typically implemented as a battery pack,which can be rechargeable or not. Sometimes a combination is used ofrechargeable and non-rechargeable battery packs. Other embodiments ofpower source 240 can include an AC power override, for where AC powerwill be available, an energy storage capacitor, and so on. In someembodiments, power source 240 is controlled by processor 230.

Defibrillator 200 additionally includes an energy storage module 250,which can thus be coupled to the support structure of the wearablesystem. Module 250 is where some electrical energy is stored in the formof an electrical charge, when preparing it for sudden discharge toadminister a shock. Module 250 can be charged from power source 240 tothe right amount of energy, as controlled by processor 230. In typicalimplementations, module 250 includes a capacitor 252, which can be asingle capacitor or a system of capacitors, and so on. As describedabove, capacitor 252 can store the energy in the form of electricalcharge, for delivering to the patient.

Defibrillator 200 moreover includes a discharge circuit 255. When thedecision is to shock, processor 230 can be configured to controldischarge circuit 255 to discharge through the patient the electricalcharge stored in energy storage module 250. When so controlled, circuit255 can permit the energy stored in module 250 to be discharged to nodes214, 218, and from there also to defibrillation electrodes 204, 208.Circuit 255 can include one or more switches 257. Switches 257 can bemade in a number of ways, such as by an H-bridge, and so on. Circuit 255can also be controlled via user interface 270.

Defibrillator 200 can optionally include a communication module 290, forestablishing one or more wired or wireless communication links withother devices of other entities, such as a remote assistance center,Emergency Medical Services (EMS), and so on. Module 290 may also includean antenna, portions of a processor, and other sub-components as may bedeemed necessary by a person skilled in the art. This way, data andcommands can be communicated, such as patient data, event information,therapy attempted, CPR performance, system data, environmental data, andso on.

Defibrillator 200 can optionally include other components.

Returning to FIG. 1, in embodiments, one or more of the components ofthe shown WCD system have been customized for patient 82. Thiscustomization may include a number of aspects. For instance, supportstructure 170 can be fitted to the body of patient 82. For anotherinstance, baseline physiological parameters of patient 82 can bemeasured, such as the heart rate of patient 82 while resting, whilewalking, motion detector outputs while walking, etc. Such baselinephysiological parameters can be used to customize the WCD system, inorder to make its diagnoses more accurate, since bodies behavedifferently. For example, such parameters can be stored in a memory ofthe WCD system, and so on.

A programming interface can be made according to embodiments, whichreceives such measured baseline physiological parameters. Such aprogramming interface may input automatically in the WCD system thebaseline physiological parameters, along with other data.

FIG. 3 is a diagram showing a collection 302 of sample components ofWearable Cardiac Defibrillator (WCD) systems, of which some are includedin many of the embodiments described in this document. The components ofcollection 302 may be included as described here, and sometimes withfurther modification for the individual embodiments, as will beunderstood from the present description.

Collection 302 includes a support structure 370 that is configured to beworn by a patient, who is not shown. Support structure 370 is shown onlygenerically in FIG. 3, and can be made as described for supportstructure 170. In addition, collection 302 includes an energy storagemodule 350, which can be configured to be coupled to support structure370. Energy storage module 350 can be made as described for energystorage module 250, and can be configured to store an electrical charge351. Moreover, collection 302 includes a discharge circuit 355, whichcan be configured to be coupled to energy storage module 350. Dischargecircuit 355 can be made as described for discharge circuit 255, and canbe configured to be coupled to energy storage module 350 and todischarge electrical charge 351 through the patient. Accordingly,discharge 371 may take place while support structure 370 is worn by thepatient.

Collection 302 also includes a measurement circuit 320, a processor 330,and a memory 338, which can be made as described respectively formeasurement circuit 220, processor 230, and memory 238. Measurementcircuit 320 can be configured to render a physiological input from apatient physiological signal, such as an ECG. It can also be configuredto render the patient impedance.

Processor 330 may control various components of a WCD system accordingto embodiments, even if not referred to explicitly. Moreover, processor330 can be configured to determine from the physiological input ofmeasurement circuit 320 whether or not a shock condition is met. If itis met, discharge circuit 355 can be configured to discharge electricalcharge 351 through the patient. In addition, a state machine 331 mayindicate an internal state of a WCD system, and may be implementedwithin processor 330, in conjunction with it, or otherwise, as is known.

Collection 302 additionally includes a user interface 373. Inembodiments, user interface 373 can be made as described for userinterface 270. In embodiments, user interface 373 may be configured tobe coupled to support structure 370, in which case the components itincludes can therefore be configured to be coupled to support structure370. In embodiments, user interface 373 may include speaker system 374that includes one or more speakers capable of outputting one or moretransmitted sounds, a screen 375 that can be configured to displayinformation, and a microphone 376 that can be configured to sense one ormore ambient sounds. In embodiments, user interface 373 can beconfigured to input data files.

User interface 373 sometimes includes a cancel switch 377 for operationsas described above. More particularly, cancel switch 377 can beconfigured to be actuated; and if it is actuated, it can preventelectrical charge 351 from being discharged, even if the shock conditionis met. Cancel switch 377 can be implemented as a mechanical pushbutton,a switch, a button displayed on screen 375, a keypad into which aspecial code may be input, a fingerprint reader, and so on. Whendischarge 371 is imminent, the patient may be warned and be given alimited time to respond, in order to prove that discharge 371 is notnecessary. This response can be made by actuating cancel switch 377.

User interface 373 sometimes includes an alerting mechanism 378.Alerting mechanism 378 can be configured to attract the attention of thepatient when activated. Such can be useful when needing the patient torespond, for example for helping with a diagnosis. In some embodiments,alerting mechanism 378 is tactile, and can vibrate. In otherembodiments, alerting mechanism 378 can be part of speaker system 374,and so on.

User interface 373 sometimes includes an inputting mechanism 379. Thiscan be implemented by any of the mechanisms described for user interface270, which permit a patient or a bystander to enter inputs that are alsosometimes called usage inputs. In some embodiments, cancel switch 377 isan example of inputting mechanism 379.

Collection 302 further includes a capacitance meter 382, which can beconfigured to be coupled to support structure 370. Capacitance meter 382may help indicate if the patient is being touched or released; in factit is often good to indicate sudden changes in capacitance from eventssuch as starting to touch and releasing.

Collection 302 further includes a motion detector 384 and a locationsensor 386. Motion detector 384 can be thus configured to be coupled tothe support structure, and to generate motion data. Location sensor 386can be configured to be coupled to the support structure, and to detecta location of the support structure.

Collection 302 moreover includes a proximity detector 380. Whenprovided, proximity detector 380 may be coupled to support structure370. Proximity detector 380 may be configured to infer a proximity tosupport structure 370 of a person other than the patient, and who is notcontacting the patient, such as a bystander.

Proximity detector 380 may be implemented in a number of ways. Forexample, it might be implemented using microphone 376. The inference canbe made by judging from what microphone 376 senses, such as speechnearby, gradually changing intensity levels from the same source, and soon. Or, proximity detector 380 may be implemented by other components,such as an illumination detector, a thermal imager, or a camera, forreceiving optical inputs. When such optical inputs change, they suggestthat a bystander is nearby and likely moving around. A thermal imagermight even work more discreetly, perhaps through a light outer garment.Or, proximity detector 380 may be implemented by a wireless signalreceiver that needs to measure only signal intensity in commoncommunication frequencies of mobile devices, such as 900 MHz in the US.When a bystander carrying a mobile communication device approaches, awireless signal receiver may be able to notice a received signal ofincreased intensity, and accordingly make a better inference. Of course,such signals may change intensity according to other patterns, such aswhen the device receives or makes a call, but the time profiles of suchintensity changes are more sudden and can be ruled out for not inferringa bystander approaching.

It is true that someone standing close could also be touching thepatient. To rule out such bystanders who are also touching the patient,proximity detector 380 may also include a touch sensor. Such a touchsensor may be implemented by a motion detector 384, since motion ofcertain time profiles may indicate touching. In addition, a touch sensormay be implemented by capacitance meter 382 and/or user interface 373 asdescribed above. When a touch sensor registers that the patient is beingtouched, proximity detector 380 can be on standby.

The above-mentioned components may be implemented in suitable places ofa WCD system according to embodiments. Some of them can be implementedwithin monitoring device 180 or monitoring device 281.

The devices and/or systems mentioned in this document perform functions,processes and/or methods. These functions, processes and/or methods maybe implemented by one or more devices that include logic circuitry. Sucha device can be alternately called a computer, and so on. It may be astandalone device or computer, such as a general purpose computer, orpart of a device that has one or more additional functions. The logiccircuitry may include a processor and non-transitory computer-readablestorage media, such as memories, of the type described elsewhere in thisdocument. Often, for the sake of convenience only, it is preferred toimplement and describe a program as various interconnected distinctsoftware modules or features. These, along with data are individuallyand also collectively known as software. In some instances, software iscombined with hardware, in a mix called firmware.

Moreover, methods and algorithms are described below. These methods andalgorithms are not necessarily inherently associated with any particularlogic device or other apparatus. Rather, they are advantageouslyimplemented by programs for use by a computing machine, such as ageneral-purpose computer, a special purpose computer, a microprocessor,a processor such as described elsewhere in this document, and so on.

This detailed description includes flowcharts, display images,algorithms, and symbolic representations of program operations within atleast one computer readable medium. An economy is achieved in that asingle set of flowcharts is used to describe both programs, and alsomethods. So, while flowcharts described methods in terms of boxes, theyalso concurrently describe programs.

In embodiments, a WCD system plays prompts in the patient's ownprerecorded voice. An example is now described.

FIG. 4 is a diagram of a scene where a patient 482 has fallen on ground403, in an emergency. Patient 482 is wearing a WCD system 402, and anouter garment 499. A bystander 483 is nearby.

From collection 302 of FIG. 3, WCD system 402 may include processor 330,support structure 370, energy storage module 350, and discharge circuit355. WCD system 402 may also include memory 338, which has beenconfigured to store at least one data file (not shown) encoding a soundrecorded in the voice of patient 482. It may also include speaker system374, which has been configured to output a transmitted sound 472.Transmitted sound 472 includes a sound 473 that has been recorded in thevoice of patient 482.

Transmitted sound 472 and sound 473 can be heard by bystander 483. Beingin the voice of patient 482, sound 473 may have a better effect onbystander 483. Depending on the sounds, bystander 483 may be protectedfrom electric shock, requested to help, and so on. For example, sound472 or sound 473 can further communicate instructions, statusinformation, a request to not touch the patient, a request to not removethe support structure from the patient, a request to say a preset wordsuch as: “CLEAR” when not touching the patient but “NO” when touching,and so on.

In such embodiments, recording for sound 473 may take place in differentways, preferably during the fitting. In some embodiments, WCD system 402may also include microphone 376, which has been configured to sense thevoice of the patient during the fitting of the device. In suchembodiments, the sensed voice becomes the recorded sound. In otherembodiments, WCD system 402 may also include user interface 373, whichhas been configured to input the data file, and the inputted data filebecomes stored in memory 338. In such a case, user interface 373 mayoperate as the aforementioned programming interface.

Transmitted sound 472 need not be only in the voice of the patient. Forone example, sounds that speak to the patient when the patient isdetected as alert can be in a voice different than his. Accordingly,memory 338 can be further configured to store another data file encodinganother sound in a voice other than the voice of the patient.Transmitted sound 472 may further include the other sound.

A related method is now described. FIG. 5 is a flowchart 500, whosemethods may be practiced by embodiments.

According to an optional operation 510, at least one data file is storedin a memory. The data file may encode a sound recorded in the voice of apatient. In embodiments where the WCD system includes a microphone,storing may be performed by sensing the patient's voice via themicrophone and recording it. In embodiments where the WCD systemincludes a user interface, storing may be performed by inputting thedata file via the user interface.

According to another operation 520, a transmitted sound is outputted.The transmitted sound may include the sound recorded in the voice of thepatient. According to another operation 530, a discharge circuit may becontrolled to discharge an electrical charge through a patient, while asupport structure is worn by the patient.

In embodiments, a WCD system is capable of sensing may sense that thepatient is being touched by a bystander, i.e. a person other than thepatient. In such cases, the WCD system may prevent discharging of theelectrical charge, so as to protect the other person, who is likely anintended rescuer. Sensing that the patient is being touched may beaccomplished in a number of ways, and two examples are now described.

In a particular embodiment, from collection 302 of FIG. 3, a WCD system(not shown separately) may include processor 330, support structure 370,energy storage module 350, and discharge circuit 355.

Such a WCD system may also include capacitance meter 382, which can becoupled to the support structure. Capacitance meter 382 can beconfigured to detect whether or not the patient is being touched by aperson other than the patient, for example while the support structureis worn by the patient. The discharge circuit can be prevented fromdischarging the electrical charge through the patient, while thecapacitance meter detects that the patient is being touched by theperson.

In another particular embodiment, from collection 302 of FIG. 3, a WCDsystem (not shown separately) may include processor 330, supportstructure 370, energy storage module 350, and discharge circuit 355.Such a WCD system may also include user interface 373 that is coupled tothe support structure, and configured to receive a usage input by aperson other than the patient. The discharge circuit can be preventedfrom discharging the electrical charge through the patient, while theuser interface is receiving the usage input.

In embodiments, a WCD system may include a proximity detector and aspeaker system. Upon inferring that no bystander is nearby, the speakersystem may sound louder, i.e. may transmit a sound at a higher intensitythan otherwise, hoping to attract attention. Examples are now described.

FIGS. 6 and 7 are diagrams of scenes for illustrating different modes ofoperation of an embodiment. Focusing first on FIG. 6, a scene is shownwhere a patient 682 has fallen on ground 603, in an emergency. Patient682 is wearing a WCD system 602, and an outer garment 699. A bystander683 is nearby, but not touching patient 682.

From collection 302 of FIG. 3, WCD system 602 may include processor 330,support structure 370, energy storage module 350, discharge circuit 355,and proximity detector 380. In the example of FIG. 6, the inferredproximity of a bystander 683 to support structure 602 is closer than athreshold. This is illustrated conceptually in FIG. 6, by showingbystander 683 as being within a physical range THR, but it should beremembered that the threshold need not be defined only in terms ofdirect distance or range. A bystander could be close in terms of directdistance, but around a corner. Rather, the threshold could be insteadcomputational, and derived by having one or more of the implementationsof proximity detector 380 “vote” as to whether they individuallydetermine that a bystander is detected to be nearby, and then accountingfor what the available votes reveal about a suitably chosen threshold.Such implementations include one or more of a microphone, anillumination detector, a thermal imager, a camera, a wireless signalreceiver, a touch sensor to exclude those contacting, and so on.

WCD system 602 may also include speaker system 374, which has beenconfigured to output a transmitted sound 672 that has a first intensity,since the inferred proximity is closer than the threshold. The firstintensity can be preferably made appropriate to the inferred proximityor distance of bystander 683.

FIG. 7 shows a somewhat different scenario. Patient 682 has fallen onground 703, in an emergency. Patient 682 is again wearing WCD system602, and outer garment 699. In the example of FIG. 7, no bystander isnecessarily detected nearby. In other words, the inferred proximity of abystander 783 to support structure 602 is farther than the threshold,shown by being outside range THR. In fact, bystander 783 might not evenbe where shown, which is why bystander 783 is shown in dotted lines. Inthat case, speaker system 374 has been configured to output atransmitted sound 772 that has a second intensity that is larger thanthe first intensity—in other words is louder. The second intensity canbe made appropriate for hailing someone, in the hope that bystander 783is actually where shown, and their attention can be attracted.

In WCD system 602, therefore, if it is determined that the inferredproximity has changed, an intensity of the transmitted sound can beadjusted accordingly, automatically. For example, the scene of FIG. 6may occur shortly after the scene of FIG. 7.

In some embodiments, the speaker system of WCD system 602 has a manualvolume setting that is configured to adjust an intensity of thetransmitted sounds. The manual volume setting can be adjustable bybystander 683, i.e. a person who is not the patient. So, if bystander783 is actually where shown, his attention is indeed attracted, and heindeed comes nearby, he can adjust the intensity of subsequentlytransmitted sounds.

Transmitted sound 672 includes a content 673, and transmitted sound 772includes a content 773. Contents 772, 773 stand for what is “said”, ifanything, during their respective sounds. Accordingly, contents 772, 773can be the sounds of a siren, a buzzer, words, prompts, and so on.Contents 772, 773 may be the same (e.g. the words: “HELP ME”), ordifferent. In some embodiments they are different depending on whetheror not the inferred proximity is closer than the threshold.

FIG. 8 shows a flowchart 800 for describing methods according toembodiments, which may also be practiced by WCD system 602 and otherdescribed embodiments.

According to an operation 810, it is determined whether or not an eventof interest to WCD system 602 is taking place, such as the emergencyevent of FIGS. 6 and 7. While such an event is not taking place,execution may circulate to other operations, and then operation 810 maybe repeated.

If at operation 810 the answer is yes, then according to anotheroperation 820, a proximity is inferred to the support structure of WCDsystem 602 of a person other than the patient. Preferably the proximityis of a person who is not contacting the patient wearing WCD system 602.Then it is inquired whether or not the inferred proximity is closer thana threshold.

If the proximity is indeed closer than the threshold, it means that thebystander is closer and, according to another operation 830, atransmitted sound is output that has a first intensity. Otherwise thebystander is farther and, according to another operation 840, atransmitted sound is output that has a second intensity that is largerthan the first intensity.

According to another operation 850, a discharge circuit is controlled todischarge an electrical charge through the patient, while the supportstructure is worn by the patient.

In addition, other operations are possible. For example, a manual volumeadjustment input maybe received, and an intensity of the transmittedsound may be adjusted responsive to the received manual volumeadjustment input.

In embodiments, a WCD system may address differently nearby bystandersthan those farther away. Upon inferring that a bystander is closer thana threshold, the speaker system may transmit a sound with a firstcontent, as opposed to a sound with a second content. Examples are nowdescribed.

FIGS. 9 and 10 are diagrams of scenes for illustrating different modesof operation of an embodiment. Focusing first on FIG. 9, a scene isshown where a patient 982 has fallen on ground 903, in an emergency.Patient 982 is wearing a WCD system 902, and an outer garment 999. Abystander 983 is nearby, but not touching patient 982.

From collection 302 of FIG. 3, WCD system 902 may include processor 330,support structure 370, energy storage module 350, discharge circuit 355,and proximity detector 380. In the example of FIG. 9, the inferredproximity of a bystander 983 to support structure 902 is closer than athreshold RG. Threshold RG could be the same or different than thresholdTHR of FIGS. 6 and 7.

WCD system 902 may also include speaker system 374, which has beenconfigured to output a transmitted sound 972 that has a first content973, since the inferred proximity is closer than the threshold. Firstcontent 973 can be preferably made appropriate to the probable mentalstate of bystander 983, such as explaining in detail, guiding them andso on.

FIG. 10 shows a somewhat different scenario. Patient 982 has fallen onground 1003, in an emergency. Patient 982 is again wearing WCD system902, and outer garment 999. In the example of FIG. 10, no bystander isnecessarily detected nearby. In other words, the inferred proximity of abystander 1083 to support structure 902 is farther than the threshold.In fact, bystander 1083 might not even be where shown, which is whybystander 1083 is shown in dotted lines. In that case, speaker system374 has been configured to output a transmitted sound 1072 that has asecond content 1073 that is different from first content 973. Thedifference between first content 973 and second content 1073 is depictedby using different shapes in FIGS. 9, 10. Second content 1073 can bemade appropriate for trying to engage someone who hopefully might bethere.

In embodiments of WCD system 902, if it is determined that the inferredproximity has changed, an intensity of the transmitted sound can beadjusted accordingly, automatically. For example, the scene of FIG. 9may occur shortly after the scene of FIG. 10.

In some embodiments, the speaker system of WCD system 902 has a manualvolume setting that is configured to adjust an intensity of thetransmitted sounds. The manual volume setting can be adjustable bybystander 983, i.e. a person who is not the patient.

In some embodiments, WCD system 902 also includes memory 338, which hasbeen configured to store one or more data files that encode a firstprompt and a second prompt. In such embodiments, the transmitted soundmay communicate the first prompt as the first content, and the secondprompt as the second content.

FIG. 11 shows a flowchart 1100 for describing methods according toembodiments, which may also be practiced by WCD system 902.

According to an operation 1110, it is determined whether or not an eventof interest to WCD system 902 is taking place, such as the emergencyevent of FIGS. 9 and 10. While it does not, execution may circulate toother operations, and then operation 1110 may be repeated.

If at operation 1110 the answer is yes, then according to anotheroperation 1120, a proximity of a person other than the patient to thesupport structure of WCD system 902 is inferred. Preferably theproximity is of a person who is not contacting the patient wearing WCDsystem 902. Then it is inquired whether or not the inferred proximity iscloser than a threshold.

If the proximity is closer than the threshold, then according to anotheroperation 1130, a transmitted sound is output that has a first content.Otherwise, according to another operation 1140, a transmitted sound isoutput that has a second content that is different from the firstcontent. Again, optionally one or more data files could encode promptsthat are communicated by the transmitted sound as the first content andthe second content.

According to another operation 1150, a discharge circuit is thencontrolled to discharge an electrical charge through the patient, whilethe support structure is worn by the patient.

In addition, other operations are possible. For example, a manual volumeadjustment input maybe received, and an intensity of the transmittedsound may be adjusted responsive to the received manual volumeadjustment input.

In embodiments, a WCD system may be able to detect whether the patientis suffering from Pulseless Electrical Activity (P.E.A.). Examples arenow described.

FIG. 12 is a diagram of a scene where a patient 1282 has fallen onground 1203, in an emergency that could be P.E.A. Patient 1282 iswearing a WCD system 1202 and an outer garment 1299. A bystander 1283might be nearby, without touching patient 1282.

From collection 302 of FIG. 3, WCD system 1202 may include supportstructure 370, energy storage module 350, discharge circuit 355,measurement circuit 320 and processor 330. Processor 330 can beconfigured to determine from the physiological input of measurementcircuit 320 whether the patient physiological signal rendered bymeasurement circuit 320 indicates that the patient could be sufferingfrom Pulseless Electrical Activity (P.E.A.).

In some embodiments, the indication of P.E.A. can be bolstered byadditional functionality. WCD system 1202 also includes motion detector384 coupled to support structure 370. In these embodiments, it can bedetermined that the patient could be suffering from P.E.A. also from amotion detector signal generated by motion detector 384. For example, ifthe motion detector signal indicates that the patient is not moving atall while still having a sinus rhythm, the cause could be P.E.A. Thechances of the ailment being P.E.A. can increase if previously there wasregular motion, which has stopped abruptly. In addition, mechanicalsigns of circulation can be checked, for example as suggested inPhysio-Control's US Patent Application 20060173499, published Aug. 3,2006.

Before determining that the ailment is P.E.A. with high certainty, WCDsystem 1202 may try to receive confirmation from the patient. Forexample, in some embodiments WCD system 1202 also includes alertingmechanism 378 and inputting mechanism 379 of collection 302. Alertingmechanism 378 may be activated responsive to determining that thepatient could be suffering from P.E.A. Alerting mechanism 378 couldoperate by voice, by a vibration, and so on. A time limit might be givento patient 1282 to respond, such as by making an entry in inputtingmechanism 379. In embodiments where inputting mechanism 379 isimplemented by cancel switch 377, making an entry would be by actuatingcancel switch 377.

Before determining that the ailment is P.E.A. with high certainty, WCDsystem 1202 may also try to engage bystander 1283 for help. Accordingly,WCD system 1202 may further include speaker system 374 coupled tosupport structure 370. In these embodiments speaker system 374 can beconfigured to output a transmitted sound 1272 that communicates arequest to check a pulse of the patient, includes the words: “PulselessElectrical Activity” or the initials: “P.E.A.”, or both.

If bystander 1283 indeed becomes engaged, perhaps no shock will benecessary. Perhaps bystander 1283 will follow the instructions, call forhelp, check the pulse, enter data in a user interface, perform CPR, andso on. In such instances, more can be done with transmitted sound 1272.For example, transmitted sound 1272 can include a transmitted soundhaving substantially periodic contents, which can be designed to assista bystander to perform CPR chest compressions on the patient while thesupport structure is worn by the patient—in other words a metronome-typesound. Additionally, transmitted sound 1272 can communicate a request tonot remove the support structure from the patient, or to say a delayingword such “NO” or “WAIT” if the patient is still touched, or to say aready word such as “CLEAR”, “YES”, or “ALL CLEAR”, after CPR is done andthe patient is no longer touched. If all goes well, shocking as a lastresort might not be necessary.

In some embodiments, if it is determined that the ailment is P.E.A. withsome certainty, and in the event that no bystander is engaging,processor 330 can control discharge circuit 355 to discharge itselectrical charge through the patient. The charge can be small, such asfor pacing, or large such as for defibrillation. Either way, WCD system1202 may thus discharge as a last resort. Indeed, if no better therapyis available, the discharge might restore the patient's sinus rhythm orchange their rhythm to one that can be restored by further shocking.Again, in such cases, discharge circuit 355 can be controlled todischarge only if no entry is received in inputting mechanism 379,responsive to alerting mechanism 378 being activated.

FIG. 13 shows a flowchart 1300 for describing P.E.A. methods accordingto embodiments. The methods of flowchart 1300 may also be practiced byWCD system 1202 and other embodiments described in this document.

According to an operation 1310, a physiological input may be rendered,for example by the measurement circuit. The physiological input may berendered from a patient physiological signal.

According to another operation 1320, it is determined from thephysiological input whether the patient physiological signal indicatesthat the patient could possibly be suffering from Pulseless ElectricalActivity (P.E.A.). This determination need not be absolute—it can be alevel of confidence. If not, which means that the level of confidence isless than a suitable threshold, then flowchart 1300 may be exited. Insome embodiments, the WCD system further includes a motion detector. Thedetermination of operation 1320 can be made also from a motion detectorsignal generated by the motion detector.

If at operation 1320 the answer is yes, then according to anotheroperation 1350, a transmitted sound can be output, for example via aspeaker system. The transmitted sound can communicate a request to checka pulse of the patient, and/or include the words: “Pulseless ElectricalActivity” or the initials: “P.E.A.”. In addition, the transmitted soundcan be and/or communicate other items, as described above.

In some embodiments, if at operation 1320 the answer is yes, thenaccording to another, optional operation 1330, an alerting mechanism isactivated. According to another, optional operation 1340, it isdetermined whether an entry is received in an inputting mechanism. Theentry would be received, for example, within a certain time period,responsive to the alerting mechanism being activated, and its receiptcould be used as an additional criterion of P.E.A. It, at operation 1340no entry is received, then execution may continue to operation 1350.Else, it may exit flowchart 1300.

FIG. 14 shows a flowchart 1400 for describing methods according toembodiments. The methods of flowchart 1400 may also be practiced by WCDsystem 1202 and other embodiments described in this document.

Flowchart 1400 includes operations 1310, 1320, 1330, 1340 that weredescribed previously, with reference to FIG. 13. However, instead ofoperation 1350, according to another operation 1450, a discharge circuitcan be controlled to discharge electrical charge through the patient.Previously mentioned additional features and extensions may beimplemented also in the methods of flowchart 1400.

In embodiments, a WCD system may request a bystander to place a mobilecommunication device close, i.e. to the speaker system, to the WCDsystem, etc. The speaker system may transmit sounds that communicateaspects of the patient and the event, and which may be thus received bya remote facility, such as a care center. Examples are now described.

FIGS. 15 and 16 are diagrams of successive scenes for illustrating how abystander may help with a mobile communication device according toembodiments. In FIG. 15 a patient 1582 has fallen on ground 1503, in anemergency. Patient 1582 is wearing a WCD system 1502, and an outergarment 1599. A bystander 1583 might be nearby.

From collection 302 of FIG. 3, WCD system 1502 may include supportstructure 370, energy storage module 350, discharge circuit 355, andspeaker system 374. Speaker system 374 can be configured to output atransmitted sound 1572. Transmitted sound 1572 may communicate a requestto bystander 1583 to place a mobile communication device proximately tothe speaker system.

While sample words are shown in FIG. 15, the request may be implementedin any number of ways. For example, the requested mobile communicationdevice may be that of patient 1582, which is to be removed from theirbody, or that of bystander 1583. For another example, the devicerequested for might not be called “mobile communication device”, butinstead transmitted sound 1572 might include enunciated words such as“PHONE”, “CELLPHONE”, “TELEPHONE”, “SMARTPHONE”, or “MOBILE PHONE”.

Additionally, the request might not be explicitly for placing the deviceproximately to the speaker system, but it could be phrased in otherways. For example, it could call for placing it close to something thatis proximate to the speaker system, such as “the patient”, and so on. Itmight even call for placing the device onto the patient, or maintain itclose to the patient but without it touching the patient at all.

In some embodiments, transmitted sound 1572 further requests bystander1583 to dial a specific telephone number on the mobile communicationdevice, prior to so placing it. This number can be “911” in the US, or anumber specifically designed for this type of occurrence.

The scene of FIG. 16 may occur shortly after the scene of FIG. 15. InFIG. 16 bystander 1583 has placed a mobile communication device 1688near patient 1582. The speaker system of WCD system 1502 now outputstransmitted sound 1672, which may be heard by cellphone 1688. Thispermits WCD system 1502 to communicate via the cellphone with a remotecare giver that has been dialed, and transmit information. Alternately,the dialed facility can be a server that merely records the transmittedsound 1672. If it is known that the dialed facility is indeed a server,the transmission can be made by machine sounds, such as DTMF, which neednot be understandable by humans.

WCD system 1502 can transmit many types of information this way. In someembodiments, WCD system 1502 also includes memory 338, which has beenconfigured to store one or more data files. The one or more data filesmay encode patient data about the patient or a medical provider relatedto the patient or WCD system itself. Transmitted sound 1672 can furthercommunicate the patient data.

In some embodiments, WCD system 1502 also includes measurement circuit320, which has been configured to render a physiological input from apatient physiological signal. Transmitted sound 1672 can furthercommunicate the physiological input. In some of these embodiments, WCDsystem 1502 further includes a processor configured to determine fromthe physiological input an ailment of the patient. Transmitted sound1672 can further communicate the determined ailment.

In some embodiments, WCD system 1502 additionally includes locationsensor 386. Transmitted sound 1672 can further communicate the detectedlocation.

During these transmissions, the attention of bystander 1583 may drift.Transmitted sound 1672 can further communicate a reminder to place ormaintain the mobile communication device 1688 proximately to the speakersystem.

WCD system 1502 may establish more of a handshake with mobilecommunication device 1688. For example, bystander 1583 may be asked topress a button on device 1688 upon initially receiving a response, andbefore placing the device as requested. Plus, instructions in humanlanguage may be received from device 1688.

In some embodiments, WCD system 1502 may receive instructions and datadirectly from device 1688, and in particular from the party that hasbeen accessed, for example in machine voice. For a particular example,WCD system 1502 may further include microphone 376 that is configured tosense an ambient sound, and state machine 331. State machine 331 can beconfigured to be in a first internal state, a second internal state, andso on, depending on what it is intended to do, such as deliver therapy,report, standby, self-diagnose, and so on. In such embodiments, thesensed ambient sound may emanate from mobile communication device 1688,and encode a command. State machine 331 may revert from the firstinternal state to the second internal state, responsive to the command.

FIG. 17 shows a flowchart 1700 for describing methods according toembodiments. The methods of flowchart 1700 may also be practiced by WCDsystem 1502 and other embodiments described in this document.

According to an operation 1710, a transmitted sound is output, forexample by the speaker system, while the support structure is worn bythe patient. The transmitted sound may communicate a request to abystander to place a mobile communication device proximately to thespeaker system. Other examples were seen above.

According to a subsequent operation 1750, the discharge circuit can becontrolled to discharge an electrical charge through the patient.Alternately, a number of optional operations may be executed, alone orin conjunction with operation 1750.

In particular, according to another, optional operation 1720, an ambientsound may be sensed, which emanates from the mobile communicationdevice. According to another, optional operation 1730, it can beinquired whether or not the sensed ambient sound encodes a command,which is likely intended for WCD system 1502. If not, execution mayrevert to operation 1720. If yes, then according to another, optionaloperation 1740, a state machine may revert from a first internal stateto a second internal state, responsive to the command.

Embodiments face uncertainties about bystanders, starting from whetheranyone is there or not. Even if someone is there, that someone is notnecessarily a person committed to helping, as is the case for someonewho rushes over to an emergency scene with an AED. Rather, a bystanderin a WCD context does not necessarily know initially that a WMS systemis already applied to the patient. This person could range anywhere froma person who is initially indifferent, to a person who may payattention, to a person who may become engaged (possibly unhelpfully), toa person who may be willing to do CPR (possibly inadequately), to aperson who may do some CPR adequately but then stop, to a trained firstresponder, to a responder who is trained for a patient wearing a WCDsystem.

A certain set of WCD system embodiments prepare for one or more of theseeventualities. Some embodiments may focus on whether or not a bystanderis willing to perform CPR and able to perform adequate CPR, andimplement dual mode operation, with switching between the modes. Ifimplemented, state machine 331 may indicate the current mode. An exampleof these modes, and switching between them, is now described.

FIG. 18 shows a flowchart 1800 for describing dual mode methodsaccording to embodiments. The methods of flowchart 1800 may also bepracticed by WCD system embodiments described in this document. It willbe appreciated that many other features described in this document canbe part of the dual mode methods of flowchart 1800.

According to an operation 1810, a WCD system detects for VentricularFibrillation (VF) or Ventricular Tachycardia (VT), or monitors for otherheart arrhythmias. For as long as no such problem is detected, executioncan loop back to operation 1810. In addition, as part of operation 1810,a WCD system may monitor for bystanders who are close, preferablypassively. Such passive monitoring may be as described in this document,for example by their voices, sounds, capacitance meter, and so on. Uponso monitoring, a system may set corresponding internal flagsaccordingly, in case a need arises.

If at operation 1810 VF or VT are detected, then operations of apossible Mode A 1820 may be performed. These operations includeadministering electrical shock therapy, which may be one shock, or astack of two or more shocks. These operations further may includere-detection of VF/VT, checking a therapy protocol for completion, andso on. Mode A 1820 may be exited upon a therapy protocol beingcompleted.

According to a subsequent operation 1830, it is determined whether abystander is available for performing adequate CPR. This can be amulti-step operation, since it may not be initially known whether or nota) a bystander is there, b) is willing to perform CPR, and c) the CPRwill be adequate. Elements of operation 1830 may include that promptsmay be issued to bystanders, bystanders may be sensed, and their CPR maybe sensed, using at least examples given in this document. It will alsobe appreciated that some of these elements of operation 1830 may beperformed also while looping through operation 1810, and also within theoperations of Mode A 1820. If at operation 1830 the answer is no, thenexecution may revert to Mode A 1820, given that there is no otheroption, or may have other protocols.

If at operation 1830 the answer is yes or maybe yes, then the operationsof a Mode B 1840 may be opportunistically performed. Of course,answering the question of operation 1830 as “yes” or “no” can beimplemented by deriving a confidence score, and determining whether theconfidence score is higher than a decision threshold. Here the decisionthreshold can be set to favor also the answer “maybe yes”, so as tofavor the opportunistic use of Mode B 1840. For example, an announcementcan be made requesting engagement, and a timer can be started. If thetimer reaches a limit without a qualifying event happening, then theanswer can become “no”, and execution may revert to Mode A 1820. Aqualifying event can be that a person's voice was heard, with someconfidence that it was in response to a prompt, or a proximity detectortriggered, or touching was detected. Of course, if a bystander engagesonly to speak and interact but not to do CPR for some prolonged timeinterval, the answer can be again deemed to be no.

Within Mode B 1840, therapy may proceed in a different mode, wheretherapy is assisted by CPR. Sequences of CPR compressions may beexpected from the bystander, who has now become a rescuer. As will beseen below, a WCD system may further have a speaker system that emitsCPR prompts so as to assist these sequences of compressions. Then therescuer may be asked to no longer touch the patient, shock, thenre-detect for VF/VT, ask for more CPR, and so on. In addition,embodiments may exit Mode B 1840 at various operations or points intime, which returns execution to operation 1830, to ensure thecontinuing availability of a bystander available to perform adequateCPR.

In such operations alerts may be set accordingly, and therapy may beenabled or disabled accordingly. Moreover, while the operations offlowchart 1800 are focused on CPR, additional prompts may ask otherbystanders for help, ask them to dial 911 and report on their own, andso on.

In embodiments, a WCD system may emit CPR prompts. A speaker system cantransmit a sound that has periodic contents designed to assist abystander to perform CPR. Such may help after a defibrillation shock,and also in the event of P.E.A. and maybe asystole, and so on.Optionally CPR chest compressions are detected, and feedback can begiven. An example is now described.

FIG. 19 is a diagram of a sample scene, where a patient 1982 has fallenon ground 1903, in an emergency. Patient 1982 is wearing an outergarment 1999. Patient 1982 is also wearing a WCD system 1902, of whichonly a small portion is shown, and in dashed lines, as it is obscured byouter garment 1999. A bystander 1983 has been engaged, and is performingCPR chest compressions on patient 1982.

From collection 302 of FIG. 3, WCD system 1902 may include processor330, support structure 370, energy storage module 350, and dischargecircuit 355. It may also have speaker system 374, which has beenconfigured to output a transmitted sound 1972. In this example,transmitted sound 1972 has substantially periodic contents 1973.Contents 1973 may be designed to assist bystander 1983 to perform CPRchest compressions to patient 1982. For example, contents 1973 may besequences of tones, to which bystander 1983 can synchronize theirsequences of compressions—in other words a metronome-type sound.Transmitted sound 1972 may further communicate a request to not removethe support structure from the patient. In addition, transmitted sound1972 can further communicate reminders to perform CPR ventilations aspart of the overall CPR. Related transmitted sounds, or images, canassure bystander 1983 that no shock is impending, that there will beample notification well before a shock is prepared, and that shock willnot happen before bystander 1983 is ready.

In a number of embodiments of WCD system 1902, CPR chest compressionsthat are performed on patient 1982 are detected. Detection may be in anumber of ways. In some embodiments, WCD system 1902 includes one ormore motion detectors 384, which can be coupled to the supportstructure. This way, the performed CPR chest compressions can bedetected by the one or more motion detectors 384. Moreover, at least oneof motion detectors 384 can be coupled to the support structure at sucha point as to be near the sternum of patient 1982, and at least one ofmotion detectors 384 can be coupled to the support structure at such apoint as to be near the back of patient 1982. Alternately or inaddition, WCD system 1902 can have an impedance sensing module, forexample from measurement circuit 320; in such cases, the performed CPRchest compressions can be detected by the impedance sensing module, asthe CPR chest compressions affect the patient impedance.

In embodiments of WCD system 1902 where performed CPR chest compressionsare detected, feedback may be additionally communicated to the user. Thefeedback may refer at least to a depth or to a rate of the detected CPRchest compressions. The feedback can be communicated in a number ofways. For example, in some embodiments the feedback is communicated bytransmitted sound 1972. In other embodiments, the feedback iscommunicated by visual representations on screen 375 on WCD system 1902.Suitable sounds and representations may be learned from the art of CPRfeedback devices.

In some embodiments, the detected CPR chest compressions are recorded,along with other events. The detected CPR chest compressions may beanalyzed, Figures of Merit may be computed, and so on. It should beremembered that, unless more is known, bystander 1983 is likely not atrained first responder, but a well-meaning Good Samaritan who may haveeven learned First Aid and CPR, but many years prior and may haveforgotten some of it.

In some embodiments, WCD system 1902 makes further provisions forshocking the patient after CPR is received. Accordingly, transmittedsound 1972 may further communicate a request for bystander 1983 to nolonger touch patient 1982. This request may be communicated after atleast two minutes of detecting chest compressions, in which case it maybe judged that patient 1982 has received some benefit from the CPR. Insome embodiments, the request to no longer touch the patient can becommunicated less than two minutes after detecting the chestcompressions, for example in cases where it is judged that the CPR ispoor, and not improving despite any prompts or feedback.

The request to not touch the patient may be communicated anyway as asafety feature, even if bystander 1983 has not yet touched patient 1982.It could be that no bystander gave CPR, but someone was preparing to doso.

In some embodiments, additional provisions for shocking the patientafter CPR can include that transmitted sound 1972 further communicates arequest to say one or more preset affirmative words, such as “CLEAR”,“YES”, or “ALL CLEAR”. It may be possible to be able to detect reliablyevery time whether bystander 1983 is no longer touching patient 1982,but engaging bystander 1983 this way may also help. In some of theseembodiments, WCD system 1902 further includes microphone 376 coupled tothe support structure. Microphone 376 can be configured to sense anambient sound, and the electrical charge can be discharged through thepatient responsive to the sensed ambient sound including one or more ofthe preset affirmative words.

FIG. 20 shows a flowchart 2000 for describing methods according toembodiments that are related to the above description. The methods offlowchart 2000 may also be practiced by WCD system 1902 and otherembodiments described in this document.

According to an operation 2010, a transmitted sound is output. Thetransmitted sound may have substantially periodic contents, which may bedesigned to assist a bystander to perform CPR chest compressions on apatient. This may be performed while a support structure is worn by thepatient.

According to a subsequent, optional operation 2020, CPR chestcompressions that are performed on the patient may be detected. This maybe performed in a number of ways, including as described above.

According to another optional operation 2040, feedback is communicatedregarding the CPR chest compressions detected in operation 2020. Thefeedback can be communicated in a number of ways, for example asdescribed above.

According to another operation 2050, a discharge circuit is controlledto discharge electrical charge through the patient. Again, this may beperformed while the support structure is worn by the patient.

In addition, what was written above for WCD system 1902 may augment themethods of flowchart 2000.

In embodiments, a WCD system may emit different CPR prompts fordifferent bystanders. The WCD system may include a user interface thatcan differentiate among bystanders. The user interface may output CPRprompts that are tailored to a skill level of the bystander. An exampleis now described.

In some embodiments, a WCD system (not shown separately) may includesupport structure 370, energy storage module 350, discharge circuit 355,and user interface 373 from collection 302 of FIG. 3. User interface 373can be configured to receive a usage input from a bystander, for exampleas described above. The usage input may relate to a skill of thebystander, as self-reported by the bystander, or looked up, or evenauthenticated.

User interface 373 may include a speaker system 374 that is configuredto output a transmitted sound having substantially periodic contents,which are designed to assist a bystander to perform CPR chestcompressions on the patient, for example as described above for contents1973. The transmitted sound may also include a request for the usageinput.

In embodiments, an aspect of the contents can be different responsive toa received usage input. A variety of implementations are possible. Forexample, the aspect can be different if a usage input is received thanif not received, and so on. The aspect can be a frequency of thecontents, a number of tones within a sequence for the compressions, anumber of sequences of compressions between shocks, a total number oftones before the next discharge that could reflect a duration of a CPRperiod, whether or not to perform ventilations, etc. For example, if ausage input by the bystander reports that the by stander is too tired todo any more CPR, no more CPR might be asked of them, and so on.

FIG. 21 shows a flowchart 2100 for describing methods according toembodiments. The methods of flowchart 2100 may also be practiced byembodiments described in this document.

According to an operation 2130, a usage input may be received. The usageinput may be received in the user interface, and be of the type that abystander enters to control a WCD system, whether unassisted or bylistening over the telephone to a remote care center.

According to another operation 2150, a transmitted sound can be output,for example via a speaker system. The transmitted sound can havesubstantially periodic contents, which are designed to assist abystander to perform CPR chest compressions on the patient. Accordingly,they can be CPR prompts, for example as described above. An aspect ofthese contents can be different responsive to the received usage input,as described above.

According to another operation 2180, the discharge circuit can becontrolled to discharge the electrical charge through the patient, whilethe support structure is worn by the patient.

In embodiments, a WCD system might be ready to deliver a shock, but maynot deliver it, if it hears a bystander say a preset delaying word suchas “NO”. An example is now described.

FIG. 22 is a diagram of a sample scene, where a patient 2282 has fallenon ground 2203, in an emergency. Patient 2282 is wearing a WCD system2202, but no outer garment. A bystander 2283 has been engaged, and isperforming CPR chest compressions on patient 2282, over WCD system 2202.

WCD system 2202 can be better prepared for this eventuality. Forexample, support structure 370 of WCD system 2202 may include anindicator pointing at a place on the sternum of patient 2282, where thepalms of bystander 2283 should be placed.

In FIG. 22, bystander 2283 is saying “NO”. (For purposes of thisdocument, a bystander saying something also includes the bystandershouting it.) When bystander 2283 speaks, he is creating an ambientsound 2284. In the example of FIG. 22, ambient sound 2284 includes theword “NO”.

From collection 302 of FIG. 3, WCD system 2202 may include processor330, support structure 370, energy storage module 350, discharge circuit355, and microphone 376. In some embodiments, WCD system 2202additionally includes a head set configured to be worn by a rescuer. Insuch embodiments, microphone 376 may be coupled to the head set. Inaddition, processor 330 can be further configured to prevent theelectrical charge from being discharged through the patient, responsiveto the sensed ambient sound including a preset delaying word. In thisexample, such a preset delaying word is “NO”, but other words can beused such as “WAIT”, etc. Since “NO” is said, discharge 371 does nothappen in the example of FIG. 22.

The bystander's saying “NO” could take place in a number of ways, forexample it can be elicited by WCD system 2202. More particularly, and aswill be seen later in this document, WCD system 2202 may have a speakersystem or a display through which it posed suitable a question, to whichbystander 2283 is replying. Here the question can be “PREPARING TO SHOCKTHE PATIENT—HAVE YOU LET GO YET?” By replying “NO”, bystander 2283 gainsmore time to release patient 2282, so that he will not be shocked alongwith patient 2282.

Processor 330 may include enough voice recognition capability forrecognizing preset delaying words and preset ready words from ambientsounds. WCD system 2202 may further include memory 338, which has beenconfigured to store one or more data files that encode one or more ofthe preset delaying words. In addition, dialogue scenarios may beplanned so that possible preset responses differ, for easierrecognition. And it should be remembered that the voice of bystander2283 may be impacted by the circumstances. Indeed, bystander 2283 may bejustifiably out of breath, stressed upon thinking that patient 2282 maydie, and possibly even frantic if patient 2282 is a loved one.Accordingly, short and clear preset words may work well, in planning thedialogue.

In a related method that may be practiced by WCD system 2202 and/or itsprocessor, an ambient sound may be sensed by the microphone. The ambientsound may be sensed while the support structure is worn by the patient.Then the discharge circuit can be controlled so as to prevent theelectrical charge from being discharged through the patient, responsiveto the sensed ambient sound including a preset delaying word.

In embodiments, a WCD system may be ready to deliver a shock, but mayfirst wait before doing so until it hears from a bystander a presetready word, such as: “CLEAR”. An example is now described.

FIG. 23 is a diagram of a sample scene, where a patient 2382 has fallenon ground 2303, in an emergency. Patient 2382 is wearing a WCD system2302, but no outer garment. A bystander 2383 has been engaged, and isnot touching patient 2382. Perhaps bystander 2383 has performed CPR onpatient 2382; while now he is no longer touching patient 2382, he isstill engaged in the event.

In FIG. 23, bystander 2383 is saying “CLEAR”. When bystander 2383speaks, he is creating an ambient sound 2384. In the example of FIG. 23,ambient sound 2384 includes the word “CLEAR”.

From collection 302 of FIG. 3, WCD system 2302 may include processor330, support structure 370, energy storage module 350, discharge circuit355, and microphone 376. In some embodiments, WCD system 2302additionally includes a head set configured to be worn by a rescuer, whocould be the bystander. In such embodiments, microphone 376 may becoupled to the head set. In addition, processor 330 may be furtherconfigured to prevent the discharge circuit from discharging theelectrical charge through the patient, but permit it to be so dischargedresponsive to the sensed ambient sound including one or more presetready words. In this example, such a preset ready word is “CLEAR”, butother words can be used such as “YES”, “ALL CLEAR” etc. Since “CLEAR” issaid, discharge 371 takes place in the example of FIG. 23.

Again, the word “CLEAR” can be elicited by WCD system 2302. WCD system2302 may have a speaker system or a display through which it posed aquestion, to which bystander 2383 is replying. By replying “CLEAR”,bystander 2383 confirms for WCD system 2302 that it is safe to shockpatient 2382.

As with the previous embodiment, processor 330 may include enough voicerecognition capability, and WCD system 2302 may further include memory338, which has been configured to store one or more data files thatencode one or more of the preset ready words. And it should beremembered that bystander 2383 may be farther from the microphone whensaying “CLEAR”, than in the previous embodiment.

It will be recognized that a single embodiment of a WCD system couldhave the features described in conjunction with both FIG. 22 and FIG.23. In such a case, the scene of FIG. 23 could simply happen after thescene of FIG. 22, for example after enough CPR.

In a related method that may be practiced by WCD system 2302 and/or itsprocessor, a discharge circuit may be prevented from discharging anelectrical charge through the patient. Then an ambient sound may besensed by the microphone. The ambient sound may be sensed while thesupport structure is worn by the patient. Then the discharge circuit canpermit to discharge the electrical charge through the patient responsiveto the sensed ambient sound including one or more preset ready words.

In embodiments, a WCD system may transmit a sound requesting a bystanderto speak. A bystander's answer may be recorded. The sensed speech may beeven interpreted for operation. An example is now described.

FIG. 24 is a diagram of a sample scene, where a patient 2482 has fallenon ground 2403, in an emergency. Patient 2482 is wearing a WCD system2402, but no outer garment. A bystander 2483 has been engaged, and isperforming CPR chest compressions on patient 2482, over WCD system 2402.

From collection 302 of FIG. 3, WCD system 2402 may include processor330, support structure 370, energy storage module 350, discharge circuit355, speaker system 374, possibly screen 375, microphone 376 and memory338. In some embodiments, WCD system 2402 additionally includes a headset configured to be worn by a rescuer. In such embodiments, microphone376 may be coupled to the head set.

In FIG. 24, speaker system 374 outputs a transmitted sound 2472.Transmitted sound 2472 may communicate a request to bystander 2483 tospeak. If bystander 2483 does speak, an ambient sound will be created,of which examples were seen in FIGS. 22 and 23. Microphone 376 may sensethe created ambient sound created by bystander 2483. In addition, memory338 may store one or more data files that contain a recording made fromthe sensed ambient sound. The one or more data files can become a recordof the event, or be discarded. For example, transmitted sound 2472 mayask about the surrounding circumstances, and so on.

The electrical charge can be discharged, in the form of a shock, beforethe transmitted sound is output, and/or afterwards. In some embodiments,the transmitted sound, before communicating the request to bystander2483 to speak, was used to assist CPR. Accordingly, before sorequesting, the transmitted sound had substantially periodic contentsdesigned to assist bystander 2483 to perform CPR chest compressions onpatient 2482, along with possibly other content.

In some embodiments, the reply of bystander 2483 is intended to berecognized without much delay. Processor 330 may include enough voicerecognition capability for this effect.

In some particular embodiments, the transmitted sound communicates arequest to say one or more preset words, so that the ambient sound ismore readily recognizable. In FIG. 24, the preset word is “CLEAR”, butof course other words are possible. Specific words chosen in advance canbe called preset words. Above examples are described of two sampleclasses of such preset words, namely preset delaying words and presetready words. Other sample preset words include “YES”, “ALL CLEAR”, “NO”and “WAIT”. In addition, the request can be displayed on screen 375, orthe request can operate in combination with what is displayed on screen375. Again, the words may be chosen in terms of context.

If the bystander indeed says one of the preset words, they may furtherhelp the operation of WCD system 2402 as these words are recognized. Forexample, the electrical charge can be prevented from being dischargedthrough the patient, responsive to the sensed ambient sound including apreset word, as seen previously for “NO” and “WAIT”. For anotherexample, the discharge circuit can be prevented from discharging theelectrical charge through the patient, but permitted to so dischargeresponsive to the sensed ambient sound including a preset word. As seenpreviously, such preset words can be “CLEAR”, “YES”, and “ALL CLEAR”.

FIG. 25 shows a flowchart 2500 for describing methods according toembodiments. The methods of flowchart 2500 may also be practiced by WCDsystem 2402 and other embodiments described in this document.

According to an operation 2510, a transmitted sound may be output, forexample via a speaker system. The transmitted sound may communicate arequest to a bystander to speak. If the bystander does speak, an ambientsound will be created.

According to another operation 2520, the created ambient sound may besensed, for example via a microphone. According to another operation2540, one or more data files can be stored in a memory. The one or moredata files may contain a recording made from the sensed ambient sound.

According to another operation 2550, discharge may take place, while thesupport structure is worn by the patient. In particular, a dischargecircuit may be controlled to discharge an electrical charge through thepatient. Variations and enrichments described with reference to FIG. 24may also be applied to the methods of flowchart 2500.

In additional embodiments, provisions can be made for the engagement ofa bystander not proceeding optimally. For example, a WCD system may havedifferent modes that it can switch to, depending on what it infers thebystander is doing. In some embodiments, if the bystander's answer isnot understood, a prompt may be repeated. Sensed ambient sounds may beexamined as to whether they are intended to be answers in the firstplace, depending on their consistency and timeliness after a prompt isissued. It is possible that a bystander will abandon the effort, inwhich case the WCD system may want to continue without help, and so on.

In further embodiments, provisions can be made for the event that thecancel switch is actuated inappropriately, for instance if the patienthas fallen on their chest in a way that presses a cancel switch buttonby the patient's own weight. For one example, it may be inferred that ifthe cancel switch is being actuated without a warning having been issuedabout it, that such an actuation is not legitimate. In such cases, therisk is that a potentially life-saving electric shock might not beadministered. Examples are now described.

In embodiments, a WCD system may include a cancel switch whose actuationcan cancel an impending shock, but it may ignore the actuation if it isinappropriate. Motion data from a motion detector may help determine ifthe actuation is inappropriate.

In some embodiments, a WCD system may include support structure 370,energy storage module 350, measurement circuit 320, processor 330,discharge circuit 355, cancel switch 377 and motion detector 384, fromcollection 302 of FIG. 3.

Motion data that is generated by motion detector 384 may be analyzed,for example by processor 330. The analysis can be as to whether themotion data supports the inference that the patient, who is wearing thesupport structure, is actually the one actuating cancel switch 377. Forexample, if the patient has stopped moving for a while, possiblyconsistently with a life-threatening cardiac event, and then cancelswitch 377 is actuated while the patient continues to be motionless, theactuation may be deemed spurious. Indeed, the actuation may be from howcomponents may contact each other, or their immediate physicalenvironment. The patient may have fallen forward on his chest. Inparticular embodiments, if it is determined that the motion data meets aspuriousness threshold, then the actuation of the cancel switch may beignored, and discharging is thus not prevented.

An actuation that is deemed spurious may be even done by a bystander,who is well-meaning but does not know better. Indeed, the bystandermight hear a warning about the impending shock, which would be intendedfor the patient while the patient is not conscious. And, not knowing anybetter, such a bystander may think that such a shock could harm thepatient. The bystander's way to protect the patient could be byactuating cancel switch 377, exactly as the warning could haveinstructed to do to prevent the impending shock. For such cases, the WCDsystem may further include speaker system 374. Speaker system 374 canoutput a transmitted sound that communicates that the actuation ofcancel switch 377 will be ignored. It can further advise a bystander tostand back, ask them to speak, and so on.

FIG. 26 shows a flowchart 2600 for describing methods according toembodiments. The methods of flowchart 2600 may also be practiced byembodiments described in this document.

According to an operation 2610, motion data is generated, for example bya motion detector. According to another operation 2620, a physiologicalinput is rendered from a patient physiological signal. The physiologicalinput may be rendered by a measurement circuit. According to another,optional operation 2630, it can be determined whether or not a shockcondition is met. The determination may be computed by a processor fromthe physiological input, for example according to criteria. If the shockcondition is not met, then flowchart 2600 may be exited.

If, at operation 2630, it is determined that the shock condition is metthen, according to another, optional operation 2640, a warning may beoutput about an impending shock that will be administered to thepatient. The warning may include words to the patient to actuate acancel switch to prevent the shock, which is a procedure that thepatient has preferably been trained upon, when first fitted with the WCDsystem.

According to another operation 2650, it can be sensed whether a cancelswitch is actuated. In the context of flowchart 2600, this sensing takesplace when the shock condition is determined to be met at operation2630. In some embodiments, the warning of operation 2640 may permit onlya fixed time interval to actuate the cancel switch. In theseembodiments, operation 2650 is deemed to have been answered as “no” ifthat time interval passes without actuation.

If, at operation 2650, it is determined that the cancel switch has notbeen actuated, then according to another operation 2680, the dischargecircuit can be controlled to discharge the electrical charge through thepatient responsive to the shock condition being met.

If, at operation 2650, it is determined that the cancel switch has beenactuated then, according to another operation 2660, it can be determinedwhether or not the motion data generated at operation 2610 meets aspuriousness threshold. The spuriousness threshold can be defined, forexample in terms of a score or a condition that is assigned to aspectsof the motion data, as per the above. If the spuriousness threshold isnot met, then the actuation of the cancel switch is deemed legitimate,and flowchart 2600 may be exited.

If, at operation 2660, it is determined that the spuriousness thresholdis met then, according to another, optional operation 2670, atransmitted sound may be output, for example via a speaker system. Thetransmitted sound may communicate that the actuation of the cancelswitch will be ignored, and the impending shock will be deliveredanyway. It may also communicate additional items, such as a warning tostand back, a request for a bystander to speak, etc. The execution mayagain proceed to operation 2680, perhaps after first giving more time,asking for another actuation, testing for spuriousness in a differentway, and so on. Operation 2680 can thus take place while the supportstructure is worn by the patient, even though the cancel switch isactuated in this context, since the motion data met the spuriousnessthreshold.

Another example is now described for ensuring that the cancel switch hasbeen actuated only by a person authorized in advance. Briefly, a WCDsystem may authenticate a person actuating the cancel switch. Moreparticularly, the cancel switch can be configured to be actuated inconjunction with receiving a correct validation input, so as toauthenticate the person who is entering the validation input. An exampleis now described.

In some embodiments, a WCD system may include support structure 370,energy storage module 350, measurement circuit 320, processor 330,discharge circuit 355, and cancel switch 377 from collection 302 of FIG.3. The cancel switch can be further configured to be actuated inconjunction with receiving a validation input entered by a person, whichmay be part of user interface 373. The person can be, of course, thepatient, plus perhaps a possible preauthorized anticipated bystander. Ifcancel switch 377 is actuated, it may prevent an electrical charge frombeing discharged even if a shock condition is met, but the electricalcharge can be so prevented only if a validation input has indeed beenentered, and the entered validation input meets a validity criterion.

The validation input may be received in a number of ways. In someembodiments, the cancel switch is made so that actuating it involvesdirectly also entering the validation input. For example, the cancelswitch may include a keyboard, and actuating the cancel switch inconjunction with receiving the validation input would accordinglyinclude entering a code in the keyboard, such as a password, a PIN, etc.The keyboard can be made by physical keys, by a touchscreen, and so on.Or, the cancel switch may include a fingerprint reader, and actuatingthe cancel switch in conjunction with receiving the validation input caninclude scanning a fingerprint of a preapproved user in the fingerprintreader. The preapproved user can be the patient, specific anticipatedbystanders, whether they know the patient or whether they have advanceclearance to render appropriate aid to this patient, etc.

In other embodiments, a validation input device is provided that isdistinct from the cancel switch. This validation input device can beconfigured to receive the validation input before or after the cancelswitch is actuated. Similarly, and as per the above, this validationinput device can include a keyboard, a fingerprint reader, etc.

In yet other embodiments, the validation input may be spoken, forexample by the patient. More particularly, the WCD system may includemicrophone 376, which is configured to sense an ambient sound. In suchcases, receiving the validation input may include sensing an ambientsound, and the validity criterion can be is that the sensed soundincludes one or more preset validation words, such as “OK”, “I AM OK”,“DO NOT SHOCK ME”, a code such as “1-2-3-4”, the last four digits of thepatient's social security number, and so on.

Thus, actuating cancel switch 377 may be deemed invalid if not enteredwith the appropriate validation input. For such cases, the WCD systemmay further include speaker system 374. Speaker system 374 can output atransmitted sound that communicates that the actuation of cancel switch377 will be ignored. It can further advise a bystander to stand back,ask them to speak, and so on.

FIG. 27 shows a flowchart 2700 for describing methods according toembodiments. The methods of flowchart 2700 may also be practiced byembodiments described in this document.

According to an operation 2720, a physiological input is rendered from apatient physiological signal. The physiological input may be rendered bya measurement circuit. According to another, optional operation 2730, itcan be determined whether a shock condition is met. The determinationmay be computed by a processor from the physiological input, for exampleaccording to criteria. If the shock condition is not met, then flowchart2700 may be exited.

If, at operation 2730, it is determined that the shock condition is metthen, according to another, optional operation 2740, a warning may beoutput about an impending shock that will be administered to thepatient. The warning may include words to the patient to actuate acancel switch to prevent the shock, which is a procedure that thepatient has preferably been trained upon, when first fitted with the WCDsystem.

According to another operation 2750, it can be sensed whether or not acancel switch is actuated, in conjunction with receiving a validationinput entered by a person. In the context of flowchart 2700, thissensing takes place when the shock condition is determined to be met atoperation 2730. In some embodiments, the warning of operation 2740 maypermit only a fixed time interval to actuate the cancel switch. In theseembodiments, operation 2750 is deemed to have been answered as “no” ifthat time interval passes without actuation. If the cancel switch hasbeen actuated, a validation input may then be requested to be entered,and perhaps the time interval can be extended somewhat.

If, at operation 2750, it is determined that the cancel switch has notbeen actuated, then according to another operation 2780, the dischargecircuit can be controlled to discharge the electrical charge through thepatient responsive to the shock condition being met.

If, at operation 2750, it is determined that the cancel switch has beenactuated then, according to another operation 2760, it can be determinedwhether or not the validation input received at operation 2750 meets avalidity criterion, for example if a code matches, and so on. If thevalidity criterion is met, then flowchart 2700 may be exited, since thecancel switch is sensed to have been actuated in conjunction withreceiving an entered validation input that meets the validity criterion.

If, at operation 2760, it is determined that the validity criterion isnot met then, according to another, optional operation 2770, atransmitted sound may be output, for example via a speaker system. Thetransmitted sound may communicate that the actuation of the cancelswitch will be ignored, and the impending shock will be deliveredanyway. It may also communicate additional items, such as a warning tostand back, a request to speak, an offer for a validation input to beentered again, etc.

The execution may again proceed to operation 2780. This may take placewhile the support structure is worn by the patient.

In embodiments, a WCD system may include a user interface that abystander can operate. Briefly, a WCD system may authenticate a personaccessing all or portions of the user interface, so as to restrictaccess only to preauthorized people. An example is now described.

In some embodiments, a WCD system (not shown separately) may includesupport structure 370, energy storage module 350, discharge circuit 355,and user interface 373 from collection 302 of FIG. 3. User interface 373can be configured to receive usage inputs from a bystander or thepatient, for example via speaker system 374, microphone 376, and/orinputting mechanism 379. Inputting mechanism 379 may also include afingerprint reader. User interface 373 can be further configured toperform acts responsive to the usage inputs, such as display items onscreen 375, generate sounds by speaker system 374, communicate with aremote care giver, etc.

User interface 373 can be further configured to receive a validationinput, which can be accomplished in a number of ways. For example,inputting mechanism 379 may include a keyboard, and the correspondingvalidation input can be a personal identification code. Or, inputtingmechanism 379 may include a fingerprint reader, and the correspondingvalidation input can include scanning a fingerprint of a preapproveduser in the fingerprint reader. In some of these embodiments, therefore,at least one of the acts is performed only if the validation input meetsa validity criterion. This way only a person with proper authorizationmay access one or more of the features, or all the features. Such aperson can be, the patient, and/or possible specific anticipatedbystanders, whether they know the patient or whether they have advanceclearance to render appropriate aid to this patient.

In some embodiments, the speaker system is configured to output atransmitted sound requesting that the validation input be entered. Thisrequest would be a reminder to someone who would have training, butmight forget it at the critical time.

In some embodiments, the speaker system is configured to output atransmitted sound having substantially periodic contents, which aredesigned to assist a bystander to perform CPR chest compressions on thepatient. These can be as described for contents 1973. In addition, anaspect of the contents can be different, depending on the usage input,which would be depending on the anticipated qualification of thebystander. The aspect can be a frequency of the contents, or a number ofhow many tones are in a sequence for the compressions, a number of howmany sequences of compressions between shocks, a total number of tonesbefore the next discharge, whether or not to perform ventilations, etc.

FIG. 28 shows a flowchart 2800 for describing methods according toembodiments. The methods of flowchart 2800 may also be practiced byembodiments described in this document.

According to an optional operation 2810, it may be requested that avalidation input be entered. The request may be made by the interface,and be audible, displayed, etc.

According to another operation 2820, a validation input may be received.The validation input may be received in the user interface, andresponsive to the request of operation 2810.

According to another operation 2830, a usage input may be received. Theusage input may be received in the user interface, and be of the typethat a bystander enters to control a WCD system. Operation 2830 may beperformed before or after operation 2820.

According to another operation 2840, it is inquired whether thevalidation input received in operation 2830 meets a validity criterion.If not, then flowchart 2820 may be exited.

According to another operation 2850, an act is performed response to thereceived usage input. There can be any number of acts, such as opening acommunication channel, turning off, switching modes, issuing CPRprompts, switching to manual defibrillation, etc. In this context, theact is performed if the validation input meets the validity criterion,else it is not performed.

According to another operation 2880, the discharge circuit can becontrolled to discharge the electrical charge through the patient, whilethe support structure is worn by the patient.

In the methods described above, each operation can be performed as anaffirmative step of doing, or causing to happen, what is written thatcan take place. Such doing or causing to happen can be by the wholesystem or device, or just one or more components of it. In addition, theorder of operations is not constrained to what is shown, and differentorders may be possible according to different embodiments. Moreover, incertain embodiments, new operations may be added, or individualoperations may be modified or deleted. The added operations can be, forexample, from what is mentioned while primarily describing a differentsystem, apparatus, device or method.

A person skilled in the art will be able to practice the presentinvention in view of this description, which is to be taken as a whole.Details have been included to provide a thorough understanding. In otherinstances, well-known aspects have not been described, in order to notobscure unnecessarily the present invention. Plus, any reference to anyprior art in this description is not, and should not be taken as, anacknowledgement or any form of suggestion that this prior art formsparts of the common general knowledge in any country.

This description includes one or more examples, but that does not limithow the invention may be practiced. Indeed, examples or embodiments ofthe invention may be practiced according to what is described, or yetdifferently, and also in conjunction with other present or futuretechnologies. Other embodiments include combinations andsub-combinations of features described herein, including for example,embodiments that are equivalent to: providing or applying a feature in adifferent order than in a described embodiment; extracting an individualfeature from one embodiment and inserting such feature into anotherembodiment; removing one or more features from an embodiment; or bothremoving a feature from an embodiment and adding a feature extractedfrom another embodiment, while providing the features incorporated insuch combinations and sub-combinations.

In this document, the phrases “constructed to” and/or “configured to”denote one or more actual states of construction and/or configurationthat is fundamentally tied to physical characteristics of the element orfeature preceding these phrases and, as such, reach well beyond merelydescribing an intended use. Any such elements or features can beimplemented in any number of ways, as will be apparent to a personskilled in the art after reviewing the present disclosure, beyond anyexamples shown in this document.

The following claims define certain combinations and subcombinations ofelements, features and steps or operations, which are regarded as noveland non-obvious. Additional claims for other such combinations andsubcombinations may be presented in this or a related document.

What is claimed is:
 1. A wearable cardiac defibrillator (WCD) system,comprising: a support structure configured to be worn by a patient; anenergy storage module configured to be coupled to the support structureand to store an electrical charge; a discharge circuit configured to becoupled to the energy storage module and configured to discharge theelectrical charge through the patient; one or more motion detectorscoupled to the support structure, at least one of the motion detectorsbeing coupled to the support structure at such a point as to be near aback of the patient while the support structure is worn by the patient;and a speaker system coupled to the support structure and configured tooutput a transmitted sound having substantially periodic contentsdesigned to assist a bystander to perform CPR chest compressions on thepatient while the support structure is worn by the patient, and in whichthe performed CPR chest compressions are detected by the one or moremotion detectors and the transmitted sound further communicates feedbackregarding the detected CPR chest compressions.
 2. The WCD system ofclaim 1, in which the transmitted sound further communicates a requestto not remove the support structure from the patient.
 3. The WCD systemof claim 1, in which the feedback refers to a depth or to a rate of thedetected CPR chest compressions.
 4. The WCD system of claim 1, furthercomprising: a screen, and in which the feedback is given also by visualrepresentations on the screen.
 5. The WCD system of claim 1, in which atleast one of the motion detectors is coupled to the support structure atsuch a point as to be near a sternum of the patient, while the supportstructure is worn by the patient.
 6. The WCD system of claim 1, furthercomprising: an impedance sensing module, and in which the performed CPRchest compressions are detected by the impedance sensing module.
 7. TheWCD system of claim 1, in which the transmitted sound furthercommunicates a request for the bystander to no longer touch the patient.8. A wearable cardiac defibrillator (WCD) system, comprising: a supportstructure configured to be worn by a patient; an energy storage moduleconfigured to be coupled to the support structure and to store anelectrical charge; a discharge circuit configured to be coupled to theenergy storage module and configured to discharge the electrical chargethrough the patient while the support structure is worn by the patient;and a user interface configured to be coupled to the support structureand to receive a usage input from a bystander, the user interfaceincluding a speaker system configured to output a transmitted soundhaving substantially periodic contents designed to assist a bystander toperform CPR chest compressions on the patient, an aspect of the contentsbeing different responsive to a received usage input.
 9. The WCD systemof claim 8, in which the usage input relates to a skill of thebystander.
 10. The WCD system of claim 8, in which the transmitted soundincludes a request for the usage input.
 11. The WCD system of claim 8,in which the aspect is different if a usage input is received than ifnot received.
 12. The WCD system of claim 8, in which the aspect isdifferent depending on a content of a received usage input.
 13. The WCDsystem of claim 8, in which the aspect is a total number of tones beforethe next discharge.
 14. A non-transitory computer-readable storagemedium storing one or more programs which, when executed by at least oneprocessor of a wearable cardiac defibrillator (WCD) system, the WCDsystem including a support structure configured to be worn by a patient,an energy storage module configured to be coupled to the supportstructure and to store an electrical charge, a discharge circuitconfigured to be coupled to the energy storage module and configured todischarge the electrical charge through the patient and a user interfacethat includes a speaker system, they result in operations comprising:receiving, in the user interface, a usage input; and outputting, via thespeaker system, a transmitted sound having substantially periodiccontents designed to assist a bystander to perform CPR chestcompressions on the patient, an aspect of the contents being differentresponsive to the received usage input; and controlling the dischargecircuit to discharge the electrical charge through the patient while thesupport structure is worn by the patient.
 15. The non-transitorycomputer-readable storage medium of claim 14, in which the usage inputrelates to a skill of the bystander.
 16. The non-transitorycomputer-readable storage medium of claim 14, in which the transmittedsound includes a request for the usage input.
 17. The non-transitorycomputer-readable storage medium of claim 14, in which the aspect isdifferent depending on a content of a received usage input.
 18. Thenon-transitory computer-readable storage medium of claim 14, in whichthe aspect is a total number of tones before the next discharge.
 19. Amethod for a wearable cardiac defibrillator (WCD) system, the WCD systemincluding a support structure configured to be worn by a patient, anenergy storage module configured to be coupled to the support structureand to store an electrical charge, a discharge circuit configured to becoupled to the energy storage module and configured to discharge theelectrical charge through the patient and a user interface that includesa speaker system, the method comprising: receiving, in the userinterface, a usage input; and outputting, via the speaker system, atransmitted sound having substantially periodic contents designed toassist a bystander to perform CPR chest compressions on the patient, anaspect of the contents being different responsive to the received usageinput; and controlling the discharge circuit to discharge the electricalcharge through the patient while the support structure is worn by thepatient.
 20. The method of claim 19, in which the usage input relates toa skill of the bystander.
 21. The method of claim 19, in which thetransmitted sound includes a request for the usage input.
 22. The methodof claim 19, in which the aspect is different depending on a content ofa received usage input.
 23. The method of claim 19, in which the aspectis a total number of tones before the next discharge.
 24. A wearablecardiac defibrillator (WCD) system, comprising: a support structureconfigured to be worn by a patient; an energy storage module configuredto be coupled to the support structure and to store an electricalcharge; a discharge circuit configured to be coupled to the energystorage module and configured to discharge the electrical charge throughthe patient; and a speaker system coupled to the support structure andconfigured to output a transmitted sound having substantially periodiccontents designed to assist a bystander to perform CPR chestcompressions on the patient while the support structure is worn by thepatient, in which the transmitted sound further communicates a requestto not remove the support structure from the patient.
 25. The WCD systemof claim 24, further comprising: one or more motion detectors coupled tothe support structure, and in which the performed CPR chest compressionsare detected by the one or more motion detectors, and the transmittedsound further communicates feedback regarding the detected CPR chestcompressions.
 26. The WCD system of claim 25, in which the feedbackrefers to a depth or to a rate of the detected CPR chest compressions.27. The WCD system of claim 25, further comprising: a screen, and inwhich the feedback is also given by visual representations on thescreen.
 28. The WCD system of claim 25, in which at least one of themotion detectors is coupled to the support structure at such a point asto be near a sternum of the patient, while the support structure is wornby the patient.
 29. The WCD system of claim 25, in which at least one ofthe motion detectors is coupled to the support structure at such a pointas to be near a back of the patient, while the support structure is wornby the patient.
 30. The WCD system of claim 25, further comprising: animpedance sensing module, and in which the performed CPR chestcompressions are detected by the impedance sensing module.
 31. The WCDsystem of claim 25, in which the transmitted sound further communicatesa request for the bystander to no longer touch the patient.
 32. Anon-transitory computer-readable storage medium storing one or moreprograms which, when executed by at least one processor of a wearablecardiac defibrillator (WCD) system, the WCD system including a supportstructure configured to be worn by a patient, an energy storage moduleconfigured to be coupled to the support structure and to store anelectrical charge, a discharge circuit configured to be coupled to theenergy storage module and configured to discharge the electrical chargethrough the patient and a speaker system coupled to the supportstructure, they result in operations comprising: outputting, by thespeaker system, a transmitted sound having substantially periodiccontents designed to assist a bystander to perform CPR chestcompressions on the patient while the support structure is worn by thepatient, in which the transmitted sound further communicates a requestto not remove the support structure from the patient; and controllingthe discharge circuit to discharge the electrical charge through thepatient while the support structure is worn by the patient.
 33. Thenon-transitory computer-readable storage medium of claim 32, in whichthe WCD system further includes one or more motion detectors coupled tothe support structure, the CPR chest compressions that are performed onthe patient are detected by the one or more motion detectors, and thetransmitted sound further communicates feedback regarding the detectedCPR chest compressions.
 34. The non-transitory computer-readable storagemedium of claim 33, in which the feedback refers to a depth or to a rateof the detected CPR chest compressions.
 35. The non-transitorycomputer-readable storage medium of claim 33, in which the WCD systemfurther includes a screen, and in which the feedback is also given byvisual representations on the screen.
 36. The non-transitorycomputer-readable storage medium of claim 33, in which the transmittedsound further communicates a request for the bystander to no longertouch the patient.
 37. A method for a wearable cardiac defibrillator(WCD) system, the WCD system including a support structure configured tobe worn by a patient, an energy storage module configured to be coupledto the support structure and to store an electrical charge, a dischargecircuit configured to be coupled to the energy storage module andconfigured to discharge the electrical charge through the patient and aspeaker system coupled to the support structure, the method comprising:outputting, by the speaker system, a transmitted sound havingsubstantially periodic contents designed to assist a bystander toperform CPR chest compressions on the patient while the supportstructure is worn by the patient, in which the transmitted sound furthercommunicates a request to not remove the support structure from thepatient; and controlling the discharge circuit to discharge theelectrical charge through the patient while the support structure isworn by the patient.
 38. The method of claim 37, in which the WCD systemfurther includes one or more motion detectors coupled to the supportstructure and a screen the CPR chest compressions that are performed onthe patient are detected by the one or more motion detectors, andfeedback regarding the detected CPR chest compressions is given byvisual representations on the screen.
 39. The method of claim 38, inwhich the feedback refers to a depth or to a rate of the detected CPRchest compressions.
 40. The method of claim 38, in which the transmittedsound further communicates a request for the bystander to no longertouch the patient.